The general focus of the proposed work is to investigate the role of neurotransmitters in the development and/or maintenance of normal structure in the nervous system of Drosophila melanogaster. To that end, we have been studying the effects on the structure and function of the nervous system of mutants which perturb the normal metabolism either of acetylcholine or of glutamate. The work outlined in this proposal seeks to improve our understanding of the genetics of the loci which code for isozymic forms of glutamate oxaloacetic transaminase, an enzyme which plays a potentially prominent role in the synthesis of transmitter-glutamate. We also intend to carry out a preliminary characterization of glutamate receptors in the fly. We will use genetic mosaics in attempt to define the spatial and temporal role of acetylcholinesterase and choline acetyl transferase in the development of the antennal sensory complex and its axonal projections to the antennal glomerulus in the brain proper. Additionally, we will carry out measurements to ascertain the effect of mutants in acetylcholine metabolism on the actual levels of acetylcholine in the fly at various stages in its life cycle.